Help me please to identify antique machinery part. Foundry pattern of a sprocket???

Dear engineers.

I have another interesting find. It looks like a foundry pattern or a mold of an unknown antique machinery part. I think it might be a final cast iron sprocket or a toothed wheel engaged with a chain in some kind of old machinery. The pattern have teeth that might be made for a chain. If you have any thoughts, please let me know since I have never seen a similar sprocket on any old machinery.

Thank you!!!

Maybe somebody can tell if those seven protrusions are teeth or something else?

Thank you.

Romak, I suspect that's not a complete pattern. If I had to guess, I'd guess there's a matching rim pattern piece split on what will be the parting line. This rim piece would have notches that match the "teeth" on the spider pattern piece you show. The rim pattern piece might be solo or there might be two pieces to be used at the same time, depending on how the foundry intended to cast the part.

You've been asking questions here about patterns and poorly identified gears, wheels, and sprockets for quite some time (years). Since you have a sustained interest in the subject, I recommend you get a hold of a basic book on patternmaking and foundry practice, as you will find it educational and will be better able to answer your own questions. Many of these texts are so old they are available free on-line, or for a nominal cost in a modern reproduction. Lindsay Publications (now retired) and Your Old Time Bookstore would be excellent places to find printed reproductions, but Google Books has many of these available as free downloads.

BTW, the black-painted bosses on the top and bottom of the spider pattern are core prints. When the spider pattern is removed from the sand, a separate sand core will be placed in the recesses formed by those black-painted parts of the pattern. The black paint is traditional patternmaking practice.

Looks like a pattern for an 1893B. Sorry, I couldn't help myself.

I looks like a bearing support. Something on a hand crank, flywheel, or a line shaft bearing retainer. Here is a link to machinery with a very large spoke and hub similar to your picture.

http://www.practicalmachinist.com/vb/antique-machinery-history/steam-engine-flywheels-112618/

It might be a multiple piece assembly for maintenance or versatility.

I googled "turbine pump bearing spider" because it looks similar to spider retainers used to hold line shafts inside a turbine pump, however your design would inhibit flow.

Thank you. I was thinking about the rim also, but it does not make sense why to cast spider-like spokes first and then a rim. At the end we will have to or even three cast iron pieces, if the rim in two parts. I saw casting patterns for flywheels and they are mostly as a single piece, rim is attached to hub and spokes. This is just my guess, but I might be wrong if the rim is not being cast and simply made of multiple pieces of wood.

I failed to communicate clearly. The casting is one piece. The pattern is two or three pieces, of which you have shown us one. The "teeth" on the spider pattern piece you showed us probably mate with notches in a rim pattern piece (or possible two such pieces). The negative sand mold is formed by all of the two or three separate pattern pieces, then a core is added where the core prints of the spider pattern piece have prepared the way.

There are several reasons why a patternmaker might make this pattern in multiple pattern pieces, as an alternative to the single-piece patterns you mention.

Extractor star for a really big Smith & Wesson revolver?

Romak,
I was reminded of this thread when I noticed this removable split rim sprocket article .
https://archive.org/stream/canadianmachiner08torouoft#page/12/mode/1up
Not a match for yours but another example of an un common sprocket.
Regards,
Jim

By the roughly involute shape to the ends of the arm, my vote would be for a drive chain tensioner sprocket or or slack side support sprocket (only there to keep the slack off the ground or fouling against other equipment.

Rich C.

Just as the core prints allow adding to the mold a core which will produce a rough bore in the casting, a two-piece rim for the patten would allow casting a rough V-groove to be machined to produce a vee-belt pulley.

Having center and rim of pattern separate also would allow mating said center to different rims, as for instance to make a flat-face pulley, or a vee-pulley, or gears or gear blanks, all of various finish diameters, all with and from the same center pattern. Very handy for jobbing foundry needing to make at short notice a variety of parts.

Romak ,
I hadn’t seen you posting for a while but noticed your recent thread .
Here are some links I found a while ago related to this thread an some of the other sprocket patterns that you had shown in other threads that I didn’t search for .
You can see a sprocket in this link that looks much like the one that the pattern in this thread may have been used for .
Perhaps not an exact match but close enough that thought it might be worth posting the links in case you would like to see them.
Canadian forest industries July-December 1919


Canadian forest industries January-June 1912


Modern power & engineering January-December 1918

Regards,
Jim

P.S.
See also.
Elevating, conveying, crushing, screening, power transmission ... - Full View | HathiTrust Digital Library | HathiTrust Digital Library

Catalog Record: Elevating, conveying, crushing, screening,... | Hathi Trust Digital Library

https://catalog.hathitrust.org/Search/Home?lookfor="Jeffrey Manufacturing Company.%22&type=author&inst=

https://babel.hathitrust.org/cgi/pt?id=uiug.30112024500024;view=1up;seq=234